Very nice cartridge - but my own measurements showed the res freq at 19kHz.... which indicates an effective tip mass of more like 0.3mg rather than 0.2mg - good... but not as good as they claimed.
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Phono Cartridge Equivalent/Effective Tip Mass Master List
- Thread starter JP
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Thank heavens for them though, (the SAS needles) don't you think?
I have a few Technics on this list... and a Stanton ... but all unobtanium now.
I remain astonished as to how good they sound. I'm just relieved I can bung on records and not worry about the tip wearing out with an old technics cartridge + SAS.
The SAS needles are keeping a whole lot of TOTL MM's in use now that their manufacturers are extinct!
dagfinn
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Do you have a source? Errors tend to multiply, these sites seem to agree on some elliptical...
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Category: Analog Dear friends: This is my first review, I’m not so good writing an audio item review but this time IMHO I think that this Technics MM p...
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16 examples here, and the Japanese product launch brochure describes an MR.Do you have a source? Errors tend to multiply, these sites seem to agree on some elliptical...
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Category: Analog Dear friends: This is my first review, I’m not so good writing an audio item review but this time IMHO I think that this Technics MM p...forum.audiogon.com
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Added.
Note: if you have a test record with signal going up high enough (20kHz run at 45rpm takes you up to 27kHz...) you can pick up most current stylus resonances....
However to properly identify it, you need to map the frequency response recorded (and correct for RIAA if relevant), and then calculate the LRC loading EQ circuit frequency impact, and deduct it from the measured frequency response.
Once you deduct the electrical EQ from the measured frequency response, you will typically see a substantial peak at the cantilever resonance frequency - the peak frequency point can then be used to calculate the effective tip mass.
Like any resonance the first peak will the the main, and there will be subsequent harmonics, if your measurement goes that high (or if the first resonance is that low!!)
This means that as long as we have a decent stylus among our community, we can measure and confirm the effective tip mass.
However to properly identify it, you need to map the frequency response recorded (and correct for RIAA if relevant), and then calculate the LRC loading EQ circuit frequency impact, and deduct it from the measured frequency response.
Once you deduct the electrical EQ from the measured frequency response, you will typically see a substantial peak at the cantilever resonance frequency - the peak frequency point can then be used to calculate the effective tip mass.
Like any resonance the first peak will the the main, and there will be subsequent harmonics, if your measurement goes that high (or if the first resonance is that low!!)
This means that as long as we have a decent stylus among our community, we can measure and confirm the effective tip mass.
undeakyetonde
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Is it possible to share a formula and some motivation for where it comes from? Thanks
dagfinn
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Second peaks@38kHz. Edit: I'm not competent to do the maths, but the Jico SAS/b is a common stylus, would be nice to know its ETM
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This is the vintage thread where I worked through it with other participants...:
Calculating / Measuring Effective stylus mass- Vinyl Engine
Outcome is this formula:
ETM =((1/(ResF*2*3.14159)^2)/[1.16 x 10^(-10)])
Balle Clorin
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What units?KHz and mg? The formula gives me a EMT of 0.5 kg for a frequency of 20 000. Is it written correctly
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Haven't looked back on that thread in years... but the end result should be in mg... would need to go through the calc to check.
At the time I used the formula to confirm/verify a number of styli that had ETM specs...
The difficult bit wasn't this formula, which I found in published white papers... but deducting the LCR response from the measured response so you can reliably identify the ResF
Balle Clorin
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But for MC there is no electrical peak in reasonable range, so MC EMT could be calculated directly?
Yes... MC's are simpler to measure as a result!
undeakyetonde
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Any idea how/where to find these papers? Is is possible you have it saved somewhere and kind enough to share?
Is it likely I have it saved somewhere - yes... the trick will be finding it!
dagfinn
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Did you look at the graph I posted? Are you in doubt of the resonant frequency in that graph? Don't think LCR response would change that, other than amplitude. Also, look at the graph of the AT24 below.
The problem of measuring ultrasonics is, a) some carts roll off early and b) phonostage must be flat to 50kHz. Second, a sweep has very little energy, so a pink noise track is more likely to show the peaks. A sweep will also present a bunch of harmonics to whatever fundamental it's playing. A pink track works better, 20kHz will do. However, if you have music tracks with sufficient energy in the HF area, it can be visible by the right sampling method, e.g. FFT of a complete LP side. It just about exciting resonances.
Audio Technica AT-24 with custom VMN40ML stylus, made by Delta667. 30kHz pink.
Not much to see in fundamentals, but that 42kHz peak is hard to miss. (From 68KHz we see Motu M4 ultrasonic noisetake over).
This is a Sony XL-35 with SAS/B. No ultrasonic peaks to see, cart rolls off.
A different way of finding ResF could be treating the cantilever as a string. We know materials, in this case boron. We know dimensions - cylinder of 0,28mm x 7mm. Lengths vary, but not much. We know the physical properties of the materials, boron, in this case.
Speeds of sound of the elements - Wikipedia
String vibration - Wikipedia
Anyone up for maths?